I had Renataki's drop off the first boss so I've been testing it out.
First impressions: Really, really inconsistent. Over the course of 23 council attempts, I had one lucky attempt where Blades uptime was 44% over 5 minutes and one unlucky attempt where I had 7.8% uptime over 4:14 (aka one proc over 4 minutes). Average uptime was 16.6% as somewhat expected, but I'd rather have consistent DPS than the odd chance to have amazing DPS every couple of pulls.
Logs here if you want a closer look.
Details for Kindath - 07-03 19:54 - Ávant Garde - World of Logs
For now, I'd stay away from Renataki's and Bad Juju; Bloodlust looks like it has a high enough PPM to be reliable; Reorigination depends heavily on your gear (but I suspect it isn't as good as it looks, given that dropping haste and crit to near zero devalues the mastery you gain).
Rough estimate: Shadopan > Bloodlust > Bottle of Infinite Stars (h) >= Rune > Bad Juju > Renataki's.
Shadowcraft should give you a decent estimation of the trinkets EP in your gear, but keep in mind that renataki's and bad juju are very low RPPM (leading to inconsistent procs) and rune may not be 100% modeled at this point.